Fabrication of Ag/AgBr/TiO2 composites with enhanced solar-light photocatalytic properties

Abstract

The TiO2 nanosheets with exposed (010) facets were synthesized via facile surfactant self-assembly. Then, the TiO2 sheets were employed as scaffolding and deposited Ag/AgBr particles via improved oil/water self-assembly method. The TEM results suggested that Ag/AgBr particles well dispersed on the surface of TiO2 sheets with diameter 1–4 nm. The modified of Ag/AgBr enhanced the absorption in the visible light region, which was due to surface plasmonic resonance (SPR) of the metallic Ag clusters formed on the surface of AgBr particle. The as-prepared hierarchical composites photocatalyst Ag/AgBr/TiO2 exhibited excellent photocatalytic activity under nature solar-light irradiation and degraded ∼91.7% of Rhodamine (RhB) within 60 min. The degradation of colorless Bisphenol (BPA) further confirmed the photocatalytic abilities of Ag/AgBr/TiO2. The quenching tests exhibited that the Ag/AgBr/TiO2 composites photocatalytic degradation organic pollutions were mainly dominated by O2− oxidation reactions, while the h+ and OH have a minor contribution. The improved photocatalytic activities can be attributed to the suitable size of Ag/AgBr particles, abundant surface active sites, effective photogenerated electron-hole pair's separation, which significantly improve the photocatalytic activity.